The fifth season of Endeavour has now come to a close, and it has been a phenomenal run of television, mixing compelling characters with engaging plots. ‘Icarus’ continues that run, offering an interesting case and a lot of emotional heft, delivering on the series’ plot threads and wrapping up on a note that means the recently-commissioned sixth season can’t come soon enough.

Morse is sent on an undercover assignment to Coldwater, a forbidding boys’ public school, with WPC Trewlove acting as his wife. His mission is to discover what happened to the man he replaced, a teacher named James Ivory, who has vanished without a trace, a case that has attracted Superintendent Bright’s attention after the mysterious death of the former investigating DI. As Morse begins to unravel the school’s secrets, the rest of the force has other things on its mind. The police station is soon to be closed, and Thursday is still thinking about retirement – his hopes of bringing down Eddie Nero and Cromwell Ames may not be realised quite as he’d hoped, however, as a tragedy rocks the station.

There was so much packed into ‘Icarus’ that it’s hard to know where to start. The case this episode is a strong one, pitting Morse against some typically unpleasant students, and his sense of decency takes somewhat of a pummelling. The staff are not particularly helpful, save the gentle Mr Bodnar (Andrew Buckley), and it soon transpires that Coldwater may not be the best place for helping fashion these young boys into men. It’s an interesting and twisty case, but it’s not really where the focus of ‘Icarus’ lies.

The Thursday plotline really came to a head this week. In perhaps the most unsurprising plot occurrence ever, Phil Daniels returned as Charlie and revealed that he had lost all of Fred’s investment money from earlier in the series. It also transpires that Charlie was pushed by the lowlifes he owed money to to use his business as a front for fraud, effectively casting a shadow over Fred for the rest of his life. When he breaks the news to Win, she is furious and leaves him – only a reconciliation with Joan helps raise his spirits as he realises his career will have to be a lot longer than he’d hoped.

The Eddie Nero-Cromwell Ames clash also hit breaking point in ‘Icarus’ – Thursday and Strange manage to track down Ames and arrest him, but they’ve nothing to hold him on. They warn Nero and Ames against doing anything rash, but neither man listens, culminating in a gunfight at Nero’s bar between two rival gangs. Although the spectre of Nero has rocked up throughout the series, Ames has been a bit of an under-developed presence – for him to be dispatched so quickly was a bit of a shame, and meant his supposed threat never really materialised.

This clash had another, more tragic element to it (spoiler alert) – after having to release Ames, Thursday gets Fancy to follow him. Fancy calls in Ames’ arrival at the bar but, when the police arrive to stop it, they find that Fancy is among the dead. Earlier in the episode, Fancy is unhappy with Morse and Trewlove’s masquerade – we see him buying a ring for her – only to be told by Morse to grow up and concentrate on his police work. This is a rebuke that he soon regrets. Fancy’s death also sets up one of the series’ lingering plot threads, as Dr DeBryn tells Morse that the bullets do not match any of the guns at the crime scene – someone else killed Fancy, and the force are determined to find out who. Trewlove, meanwhile, puts in a transfer request – it will be a shame to say goodbye to Richards, who has frequently been the only person on par with Morse.

‘Icarus’ is a strong end to a very strong series of Endeavour – we have a case, but the emotional heft is what carries this episode. It really speaks to the incredible scripts and the top-quality acting (Shaun Evans and Roger Allam have been amazing leads) that we care so much about these characters and what will happen to them. The sixth season cannot come soon enough.